Vocabulary learning is arguably one of the most salient, important, difficult and long-lasting tasks in language learning. Deliberate efforts in learning vocabulary strategically may make the learning process more efficient, effective, and even more pleasant.

Vocabulary learning strategies (VLS) are learners’ conscious efforts in managing their own learning of vocabulary in order to make it more effective and more efficient, in increasing their vocabulary size and depth, and in being able to use the vocabulary learned automatically and appropriately. Strategic vocabulary learning is an intentional, dynamic and iterative process. It is normally triggered by a difficult or novel vocabulary learning task. We start by noticing a vocabulary item or chunk and then focus our attention on it. Next, we quickly analyse the learning task, ourselves as learners and the learning environment before we form an attack plan. The plan is then executed, and we monitor its effectiveness along the way and evaluate its degree of success in achieving the learning goal. Often this evaluation will necessitate a re-analysis of the task and redeployment of strategies, making strategic vocabulary learning a spiraling and complex problem-solving process.

Whenever a new, important or difficult task is identified, strategic learners go through the choice, use, and evaluation of strategic learning cycles. This means that the nature of the learning task is important in determining what strategies are the most appropriate and most effective. At the same time, who the learner is and what strategy repertoire is available determine what strategies are triggered. Whether a strategy is needed and how effective it is are influenced by contextual affordances and constraints as well.

Research on vocabulary learning strategies in second language acquisition started in the late 1980s. Three decades of research on vocabulary learning strategies have produced very fruitful findings that are now guiding the practices inside the language classroom. Many exploratory studies have resulted in the discovery of naturally occurring strategies second language learners normally use for learning vocabulary. These have resulted in the compilation of a number of strategy indices. Questionnaire studies making use of these indices have been able to establish how vocabulary learning strategies are related to vocabulary size and general language proficiency. It has also been found that the choice, use, and effectiveness of VLS are mediated by task, learner, and contextual factors, and that the configurations of factors and relationships are complex, dynamic, and situated.

The following list of ten research questions help to strengthen existing research findings and shift our efforts from surface-level explorations to more in-depth examinations and explanations. The last research question also highlights the need for the application of our research findings.